I just bought 2.5 terabytes of hot-swappable SATA-300 storage for $730. If I count only the cost of the 500-GB hard drives at $120 each, I'm getting 4166 MB of storage for every dollar. Fifteen years ago, I got 0.4 MB for every dollar and that's not even adjusted to inflation. That's more than 10,000 times the storage for the same dollar, not adjusted for inflation.

Here are the five 500-GB Seagate hard drives with the hot-swap drive cage.

The AMS DS-3151SSBK hot-swap SATA drive cage fits inside a normal PC chassis using three contiguous 5.25" drive bays, and it holds five 3.5" SATA hard drives. There are plenty of LEDs in the front to show you drive activity, fan, and power.

Photos: How five 500-GB hard drives stack up

In 1992, I drove 70 miles to snag a 200-megabyte IDE hard drive for $499. This weekend I bought 2.5 terabytes of hot-swappable SATA-300 storage for just under $730. That's more than 10,000 times the storage for the same dollar.

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I just bought 2.5 terabytes of hot-swappable SATA-300 storage for $730. If I count only the cost of the 500-GB hard drives at $120 each, I'm getting 4166 MB of storage for every dollar. Fifteen years ago, I got 0.4 MB for every dollar and that's not even adjusted to inflation. That's more than 10,000 times the storage for the same dollar, not adjusted for inflation.

Here are the five 500-GB Seagate hard drives with the hot-swap drive cage.